{"id":8714,"date":"2017-03-21T10:38:00","date_gmt":"2017-03-20T23:38:00","guid":{"rendered":"https:\/\/www.homebrewradio.us\/blog\/2017\/03\/21\/fb-ibew-hb-dc-cw-de-uae-a65dcs-international-homebrew-rig\/"},"modified":"2025-07-22T01:11:38","modified_gmt":"2025-07-21T15:11:38","slug":"fb-ibew-hb-dc-cw-de-uae-a65dcs-international-homebrew-rig","status":"publish","type":"post","link":"https:\/\/www.homebrewradio.us\/blog\/2017\/03\/21\/fb-ibew-hb-dc-cw-de-uae-a65dcs-international-homebrew-rig\/","title":{"rendered":"FB IBEW HB DC CW de UAE: A65DC’s International Homebrew Rig"},"content":{"rendered":"
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Good evening!<\/b> <\/p>\n

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After my JOO moment, Bill put me in contact with Pete Eaton, who suggested that I would have a look at the schematics for K4GC 40m CW Transceiver.<\/b><\/div>\n
And I did, It was just perfect for me, low part count, lots of things done in software!!! Perfect Bryan!<\/b><\/div>\n
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http:\/\/www.k4gc.com\/40mdirectconversionxcvr061516.html<\/b><\/a><\/div>\n
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I started off the build and both Bryan and Pete supported me along the way, thank you! <\/b><\/div>\n

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So here we have it:<\/b><\/div>\n
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The design slowly deviated further and further from the original, but I think I learned quite a lot by starting to make it \u201cmy own\u201d.<\/b><\/div>\n
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The Arduino was changed to an UNO, yeah they are clunky and big, but I was not shooting for a pocket-size anyway\u2026 and they do have a proper USB port.<\/b><\/div>\n
The RF-path is now switched by a relay straight after the filter, when the relay is relaxed the antenna is connected to the mixer, when I touch a paddle it connects to the TX circuit.<\/b><\/div>\n
I have a short hang time from the last key input and it goes back to RX, VOX Delay I guess.<\/b><\/div>\n
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I completed the 700Hz bandpass filter, boy! this makes it a much nicer rig to work CW, I originally I skipped this filter for no good reason? That is the board standing up in the picture.<\/b><\/div>\n
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The TX circuit is a two stage, the first stage is a replica of VK3YE beach40 amplifier circuit, that also uses DB139. The second stage is a spin of the EMRFD Page 2.38 IRF511 Amp.<\/b><\/div>\n
I have cranked it up to 17w, but it gets too hot too fast, as you can see I don\u2019t have any proper cooling yet, I need to redo this board and plan for the heatsink a bit better.. it is now set around 10w, still getting hot, “599 TU 73\u201d.<\/b><\/div>\n
To be honest my CW does not go much further anyway, but I guess with this radio now completed I have one more reason to get my speed up.<\/b><\/div>\n
I use for convenience both CLK0 and CLK1, when I go into TX I switch off CLK0 and do the keying on CLK1, both transmitter stages are powered up the whole time (until I stop keying as described above)<\/b><\/div>\n<\/p><\/div>\n
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As the 700Hz filter worked so superb, I decided that I wanted to introduce \u201cmodes\u201d to the rig, I can now switch the audio either thru the filters (CW) or straight to the AF amp (AM).<\/b><\/div>\n
I do enjoy listening around, and we have a lot of AM stations on offer in my region.<\/b><\/div>\n
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I kept the smart RX mute transistor circuit and when I ask the Arduino to change mode, it will mute the receiver quickly, pull the relay and then un-mute again, no ear pain from the loud relay click. (I am happy with that detail).<\/b><\/div>\n
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The 2 line display became a four line, and I can change Tuning Rate, RIT, Key Speed and Mode by using only the encoder and the one button built into the encoder.<\/b><\/div>\n
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The front panel sports, on off, Headphones, Paddle and volume, the display and the big knob.<\/b><\/div>\n
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Power connector and USB Port on the side. I did complete the CAT control changes while working on this radio, it now uses the classic Kenwood interface e.g. TS480. (A lot fewer questions from the PC to answer.)<\/b><\/div>\n
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The CAT control works very nice while using N1MM, it works a lot less nice using CQRLog, I guess it has to do with the number of times the software in the PC is asking about things from the radio.<\/b><\/div>\n
I will look into logic to only worry about incoming serial requests if I have not answered for some time, and never answer while in TX\u2026<\/b><\/div>\n

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By pressing the VFO button a small arrow appears next to TR, if I push again it moves the arrow down to RIT and so on.<\/b><\/div>\n
if I turn the knob with the arrow standing in front of e.g. KEY it will increase or decrease the KEY speed, when I press again, it will return to frequency control.<\/b><\/div>\n
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Oh, another detail (that I am happy with) while the arrow is in front of the KEY, you can fiddle with the paddle with out transmitting.. practical for testing the speed.<\/b><\/div>\n
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So this is a K4GC transceiver with bits and pieces from VK3YE and bits from the A65DC laboratory in Dubai, truly international.<\/b><\/div>\n
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To trim things in I scheduled a QSO with a local ham here, and things worked very nice, later the same night I made my first \u201cDX\u201d contact with RM2D!!! Moscow!!<\/b><\/div>\n
What are the odds that a Swedish guy living in the UAE makes the first contact to another Swedish ham who lives in Russia!<\/b><\/div>\n

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73,<\/b><\/div>\n
Martin A65DC<\/b><\/div>\n<\/p><\/div>\n<\/p><\/div>\n
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Good evening! After my JOO moment, Bill put me in contact with Pete Eaton, who suggested that I would have a look at the schematics for K4GC 40m CW Transceiver. And I did, It was just perfect for me, low part count, lots of things done in software!!! Perfect Bryan! http:\/\/www.k4gc.com\/40mdirectconversionxcvr061516.html I started off the … Continue reading “FB IBEW HB DC CW de UAE: A65DC’s International Homebrew Rig”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":5288,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[67,116,35,36,96,318,451],"tags":[],"class_list":["post-8714","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-arduino","category-cw","category-direct-conversion","category-parker-peter","category-russia","category-sweden","category-uae"],"_links":{"self":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8714","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/comments?post=8714"}],"version-history":[{"count":1,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8714\/revisions"}],"predecessor-version":[{"id":8715,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/posts\/8714\/revisions\/8715"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media\/5288"}],"wp:attachment":[{"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/media?parent=8714"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/categories?post=8714"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.homebrewradio.us\/blog\/wp-json\/wp\/v2\/tags?post=8714"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}